Iowa Sen. Chuck Grassley has gained an enthusiastic Twitter following though his bizarre tweets about hitting deer with his car and the messy psychological aftermath, so it’s easy to forget that the senator is, well, a senator. Grassley was one of the few who pursued an investigation into the Obama administration’s botched Fast and Furious gun walking operation, and he’s pleased to see some results at last.

Heads are beginning to roll nearly two years after the Fast and Furious gunwalker scandal first came to light. William McMahon, the Bureau of Alcohol, Tobacco and Firearms (ATF) official who was in charge of field operations during the controversial operation, has been fired, according to his attorney Mark Zaid who told CBS News “we will be appealing the decision.”

Other ATF managers reportedly face similar fates, and announcements could be made soon, though neither they nor their attorneys would confirm it. They are: Mark Chait, who was ATF’s assistant director for field operations; Bill Newell, who was ATF’s Special Agent in Charge of Phoenix; and George Gillett, Newell’s second in command.

Grassley’s tweets seem to have attracted an unusually large number of trolls with Bob Costas fever.

@ChuckGrassley I thought guns didnt kill people, people do. Nevermind, anyone that says that is an extraordinry IDIOT.